Seen This Week: Colorful Leaves, a White Cocoon and Pine Siskins

Red sweetgum leaves in Oakland neighborhood, 20 October 2026 (photo by Kate St. John) 26 October 2026 Fall leaf color has been weak this month. The maples turned red early but their leaves were blown off in strong winds about a week ago. In the city’s urban heat island, the oaks have not changed yet so it was a relief to find bright red sweetgum leaves in Oakland (at top). Leaves were still green in Schenley Park last Friday, though the sun rays were a nice touch. Sun rays at Schenley Park, 23 Oct 2026 (photo by Kate St. John) Insects are getting ready for winter. Last week I found a caterpillar heading down the curb into the street. Google Lens said it’s a yellow-striped armyworm (Spodoptera ornithogalli), a food generalist that pupates underground. This one was in for a rude awakening when it found asphalt beneath the fallen leaves. In farming country this caterpillar is a pest because it eats crops. Yellow-striped armyworm caterpillar, Bayard Street in Pittsburgh, 21 Oct 2026…